Diaphragm pump



FIG. 1 is a front view of a diaphragm pump showing our design;

FIG. 2 is a left side view;

FIG. 3 is a right side view;

FIG. 4 is a top view; and,

FIG. 5 is a bottom view.

The back view is identical to the front view.

The broken line showing of four sets of circles in FIG. 2, two sets of circles in FIG. 3 and their corresponding side views in FIGS. 1, 4 and 5 as well as the mounting slots in FIGS. 2, 3, and 5 are for illustrative purposes only and forms no part of the claimed design. 

The ornamental design for a diaphragm pump, as shown and described. 